Presser-foot mechanism for sewing-machines.



E. ERICKSON. PRESSEB FOOT MEGHANISM FOR SEWING MACHINES.

APPLIOATION FILED APE. 21, 1913.

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MM" MM N Pieilllhilpl@ @hilliillmi EDWARD ERICKSON, OF LYNN,MASSACHUSETTS, ASSXGNOR T0 VCTOR- SHOE MACHINERY COMEANY, 0F BOSTON,MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

speciacation bf Letters raient.

Patented Maiz 23, 19915.,

Application filed Aprili21, 1913. Serial No. 762,729A

To all 'whom it may concern Be it known that l, .EDWARD ERICKSON, asubject of the. King of Sweden, and a resident of Lynn, in the county ofEssex and State of Massachusetts, have invented certain new and usefulImprovements in Presser-Foot Mechanisms for Sewing-Mau chines, of whichthe following is a specificetion.

This invention relates to shoe sewing machines and particularly to thepresser foot mechanism and means automatically controlled by theoperation of the presser foot mechanism for measuring the requiredlength of thread for varying thicknesses of material.

It consists of certain novel features of construction and arrangement ofparts which will be fully understood by reference to the description ofthe drawing and to the claims hereinafter given.

The drawing consists of a transverse section of a sewing machine showinga presser foot mechanism and thread measuring mechanism controlledthereby, said mechanisms embodying the features of the presentinvention. Y

In thedrawing, 10 is a framework having mounted thereon the revolubleshaft 11, tov-Which is keyed a disk 12 having formed therein the campaths 13 and 14:. ln the cam path 13 is a roller 15 mounted upon a studin the end of a lever 16 movable about a piwot 17 mounted in the frame10. This pivot, 17 is adapted to be oscillated in the frame 10 andisprovided with peripheral teeth forming a pinion 18. The outer end of thelever 16 is provided with a guideway having parallel guide-walls 19-19extendin transversely of said lever. Interposed etween the guide-walls19--19K is a slidable member 20 having formed therein rack teeth 2lengaging with the peripheral teeth of the pinion 18. Secured to theslidable member and extending laterally therefrom is the member 22, towhich is secured the presser foot 23, the lower end of which has anoperating face 24 parallel with the upper face 25 of the work support26. In the drawings the presser foot is shown in the position assumedwhen no work is being acted upon. lt; is obvious that when the slidablemember 20 is moved transversely of the outer end of the lever 16 thelower face 24 of the presser foot 23 and the upper face 25 of the worksupport 26 will remain constantly in parallelism when in grippingcontact with the work in whatever position the presser foot may assume,1t being understood that when said lever 16 is moved about its pivot bythe throw of the cani 18 the face 2,4 is free from gripping pressureupon the work. rlihis` is of great advantage, as by means of thisconstruction the operating face 24 of the presser foot 23 when grippingthe supported work always has an equal grip thereon, while in otherforms of presser foot mechanisms when the position of the presser footchanges the operating face 24: is inclined so that the gripping surfaceis continually being diminished. Secured to the fulcrum member 17 is anarm 27 adapted to be manually controlled to adjust the presser foot 23relative to the lever 16, and to accommodate it to varying thicknessesof material. This is accomplished by the operator moving the arm andturning the pinion 18, raising and lowering the presser foot 23 at will.The movement of the slidable member 2O in one direction is limited bythe member 22 coming in contact with the shoulder 28 on the lever 16while the movement in the opposite direction is controlled by means ofthe spring 29 surrounding a guide rod 30 extending upwardly from themember 22 and through a hole in the member 31 secured to the lever 16,said hole being larger than the rod 30. The spring 29 is so light thatit simply retains the face 24fof the presser foot 23 in light contactwith the work but does not create any effective pressure thereon, theonly positive pressure upon the work being that created by the cam path13.

To permit work to be placed upon the work support 26, it isV necessary,by means of the arm 27, to lift the presser foot 23 against the tensionof the spring 29, thus separating the members 22 and 16. As soon as thework is properly positioned the menilfer 20 will be moved downwardly bythe spring 2f) and the presser foot 23 will foot 23 in gripping Contactwith the work upon the support 26, but when it is desired to move thework 'along the' support the roller 15 of the lever 16 moves into theportion 32 of said cam path 13, thereby caus ing the gripping pressureof the presser foot to be removed from the work temporarily while saidwork is being moved upon the support into a new position.

When the cam throw 32 operates upon the. lever 16 to move its front endupwardly the gripping pressure of the presser foot will be removed fromthe work, and while the roller 15 remains in the throw 32 the onlypressure upon the presser foot will be that of the light spring 29surrounding the rod 3Q which will retain the presser foot in lightcontact with the work. This light pressure will not prevent the feedofthe work be.- neath the presser foot when the material is ofsubstantially the same thickness or when it decreases in thickness asfed. When the material decreases in thickness the spring 29 will movethe presser foot down to a new position without effecting any change inthe position of the lever 16. lVhen as fed the material increasesslightly in thickness, the presser foot will be forced further into thework. Vhen any material increase in the .work occurs as'it is fed theposition of the presser foot must be changed by the operation of thearm27. The slide 20 tits closely the guide walls 19, 19x, and there isusually sutlicient friction between the contacting surfaces to permitthe presser foot to be raised from the work when the roller 15 entersthe throw 32 and the work will be fed before the spring 29 will o ercomethe friction and force the presser foot downwardly into light contactwith a pew portion of the surface of the material. While the presserfoot is bearing upon the work the awl pierces the material from theunder si de and tends to lift the material from the work support, andwhen the awl has pierced the material but before it has finished itsstroke,

' the presser foot will be lifted, the movement `of the lever 16permitting the material t0 be llflifted from the support by thecontinued upward movement of the awl. At this time the feed takes placeand the increased space between the presser foot and work support atthis time takes care of the varying thicknesses of material withincertain limits. W'hen the awl is Withdrawn the spring 29 acts to forcethe material into contact with the work support and the presser footinto contact with the wrk. This movement ofy the front end of the lever16 upwardly relatively to the member 22 closes partly the Space betweenlthe members 22-16 so that when the cam 13 next operates upon the lever16 the face 24 of the presser foot 23 will be moved downwardly below itsformer position, therebyefecting a gripping pressure upon the work. Thevarious cycles of the cam 13 will then cause the presser foot tooscillate from a gripping position to a nongripping position and viceversa. lf the work is of the same thickness throughout the relativepositions of the lever 16 and member 22 will remain unchanged but if thethickness of the material varies, the relative positions of the member22 and lever 16 will be changed automatically in the manner justdescribed. For instance, if the material becomes thinner as it is fedthe presser foot 23 will be moved into light contact with the work bythe action of the spring 29, thus decreasing the space between themember 22 and lever 16, but when the throw 32 again moves the lever 16about its pivot to lower the presser foot 23 the gripping pressurethereon will be uniform with that upon the thicker part of the material.In other words, the presser foot will be adjusted automatically to adaptit for various thick` nesses of material, but when the gripping pressureis given by a fixed cam throw B2, the gripping pressure will always beuniform without regard to the thickness of the material being actedupon.

When the lever 16 is moved about its pivot in either direction by thecam throw 32 the relative position of the member 22 thereto will not bechang d by any power applied to said lever, the changes in the relativepositions of the lever 16 and member 22 being effected always by powerof the spring 29 which returns the face 2t of the presser foot 23 'intocontact with the upper face of the material being fed beneath it, thisbeing true whether the material is increasing or decreasing inthickness. It must be understood that at the time of feeding thematerial, the pressure of the presser foot thereon is reduced to aminimum.

While the slide 2O may be moved rela tively to the lever 16, it isobvious that when the cam 13 acts on the left end of the lever 16 thislever will be moved about its pivot 17 and carry the members 22-23therewith, the presser foot 23 being caused thereby to give a grippingpressure upon the work on the support 26. This action is due largely tothe location of the pivot 17 adjacent to the sliding member 20 so thatwhen said' lever 16 is moved about its pivot while the presser foot 23is in contact with the work the slide 20 will be cramped between theguide walls 19-19 c on the lever 16 and b v this cramping operation saidslide will be prevented from moving transversely of the lever 16. Conseuently when the left hand end of the leverhis moved upwardly by the cam13, the operating face 24 of the presser foot 23 will be forced into theyieldin material upon the work support 26 and rmly 50 lever 36 willcoact with the tglldddltd@ lo ber 2O passing through any suitable waxpot,

any wellknown take-up device, and then through the Work support 26 tothe work. As these mechanisms form no part of the present invention, andany Well-knovvn oonstructions may be used, they are not illustrated inthe drawing.

lin the slot 33 is adapted to move the pin 35 mounted in the extreme endoit a lever 36 pivoted at 37 to the frame l0 4and pro- 2o vided at itsop osite end with a truck or roller 38 .exten ing into the cam path lt.l This lcam path is provided with a throw adapted to oscillate the lever36 at the proper time to measure off the given quantity et thread forthe stitch, the pin 35 in doing this moving longitudinally ot the slot33. The thread 341i in crossing the slot 33 passes beneath the stad orpin 35 and it is obvious that it the slidable member 20 was always inthe same position a given of thread would always be measured by theoscillation of the lever 36 and the movement of the ,pin in the slot 33.lt is desired, however, to measure off different lengths of thread for35 different thicknesses of material, and this is readily accomplished`by rneans of the slidable member 20, it being self-evident that when.the presser toot 23' is raised the thread-carrying passages in thelower end 410 of the slidable member are similarly raised into a newposition corresponding with the thickness of the material and when inthis raised position a greater quantity of thread will be drawn from thesource of supply by the movement of the pin 35 in the slot 33, thelower-most position of said in being thev same under all conditions. Wen the takeup device is operating, the pin 35 will be in its highestposition and the in 40 on the xed pin 4l to clamp the thread to preventit being fed. llt is obvious, therefore, that not only does the presserfoot 23 accommodate itself automatically to varying thicknesses ofmaterial on the work support 26 but it automatically provides at thesame time for varying lengths of threads corresponding to thethicknesses of material through which the thread is to be fed.

lt is believed that the operation and many 55 l. rllhe combination of apivoted cam-con trolled lever provided with parallel guida walls;amember supported by said lever and movable concentrically therewithabout its pivot adapted to be reciprocated endwise between andlengthwise of said guide Walls; a work support; and a presser footsecured to said reciprocating member.

2. The combination of a pivoted campeon trolled lever; a member carriedthereby and slidable transversely thereof; a work support; and a presserfoot secured to said slidable member. f

3. The combination of a pivoted camcomtrolled lever; a member carriedthereby and slidable transversely thereof; a work S11 port; a presserfoot secured to said slidabl member; and means for moving said slidablemember independently of said lever.

, 4. The combination of a pivoted cam controlled lever; a slidablemember normally `positioned thereon and movable therewith.;

a work support; a presser foot secured to said slidable member; andmanually con trolled means for mov' said sl-idable member transverselyof said ever.

5. The combination ot a pivoted camlcontrolled lever; a slidable membernmmally positioned thereon and movable therewith, said membm beingprovided with rack teeth; a work support; a presser foot secured to saidslidable member; a pinion at the pivotal axis of said lever engagin saidrack teeth; and means for rotating said pinion.

6. The combination ot a pivoted cam-controlled lever; a slidable membernormally positioned theneen and movable .tl-.1er,evv'ithe said memberbeing provided with rack teeth; a 'work support; a pnesser toot sevcured tto said slidable member; a pinion at the pivotal axis of saidlever engaging said rack teeth; and a manually controlled arm forrotating said pinion.

7. The combination of a pivoted cam-con trolled lever having a guide-wayextending transversely of its outer end; an oscillating fulcrum for saidlever provided with peripheral teeth; a member slidable in saidguide-way having rack teeth engaging the teeth on said ulcruin member;means for limiting the movement of said slidable member in onedirection; a spring adapted to move said member in the oppositedirection;

a work support; and a presser foot on saidI slidable member.

8. .The combination of a pivoted cam-controlled lever having atransversely disposed guide wall at its outer end; an oscillatingfulcrum provided with a pinion; a spring controlled slidable memberinterposed between said guide wall and pinion having rack teethengaging? the teeth of said pinion; a work suppor and a presser foot onsaid slidable member.

9. The combination of a-pivoted cam-controlled lever; a slidable membercarried iso thereby-and movable transversely thereof at a pointintermediate the pivot and outer end; a presser foot on said slidablemember; a Work support; and means for moving said slidable memberendwise.

10. The combination of a pivoted camcontrolled lever; a Work support; apresser foot carried by and movable with said lever; means for adjustingthe position of said presser foot relative to said lever; and meanswhereby the operating face of said presser foot may be retained in allpositions parallel to the upper face of said support while work grippingpressure is being applied thereby.

11. The combination of a pivoted camcontrolled lever; a work support; apresser foot carried by and yieldingly connected to said lever adaptedto be moved substantially vertically from said work support; means alsocarried by said lever adapted to retain said presser foot in Contactwith the Work on said support; and means whereby Workgripping pressuremay be imparted to said presser foot. l

12.7The combination of a pivoted camcontrolled lever; a Work support;and a presser foot yieldingly connected to the free end of said leverand having a transverse reciprocating movement relative thereto. adaptedto be moved with it away from the Work support; means for moving saidpresser foot in the opposite direction into contact with the work onsaid support; and means Whereby Work-gripping pressure may be impartedto said presser foot by a continued movement of said lever to its normalposition.

13. The combination of a pivoted camcontrolled lever; a forked memberslidable thereon adapted to guide a thread across the slot of saidforked member; a work support; a presser foot secured to said slidablemember; and a reciprocating thread engaging member operating in saidslot to pull a required length of thread from the supply.

14:. The combination of a pivoted calncontrolled lever; a member carriedthereby and slidable transversely thereof; a Work support; a presserfoot secured to said slidable member; and a thread measuring devicecoacting with said slidable member and adapted to measure varyinglengths of thread corresponding to the thickness of the material beingoperated upon.

15. The combination of arloivoted camcontrolled lever; a member carriedthereby and slidable transversely thereof; a work support; a presserfoot secured to said slidable member; a thread measuring device; andmeans whereby said slidable member may be moved independently of saidlever and its position varied relative t0 said measuring device so thatvarying lengths of thread may be measured according to the varyingthicknesses of material.

Signed by me at 4 Post Oice Sq., Boston1 Mass., this 18th day of April,1913.

EDWARD ERICKSON.

Witnesses:

WALTER E. LOMBARD, NATHAN C. LOMBARD.

